Association between low-to-moderate fluoride exposure and bone mineral density in Chinese adults: Non-negligible role of RUNX2 promoter methylation.

Bone mineral density (BMD) changes were reported to be associated with excessive fluoride exposure and abnormal expression of RUNX2. However, whether the alteration of methylation status, a most commonly used marker for the alteration of gene expression in epidemiological investigation, of RUNX2 is associated with low-to-moderate fluoride exposure and BMD changes has not been reported. Our study aims to explore the role of RUNX2 promoter methylation in BMD changes induced by low-to-moderate fluoride exposure. A total of 1124 adults (413 men and 711 women) were recruited from Kaifeng City in 2017. We measured BMD using ultrasound bone densitometer. Concentrations of urinary fluoride (UF) were measured using ion-selective electrode, and the participants were grouped into control group (CG) and excessive fluoride group (EFG) according to the concentration of UF. We extracted DNA from fasting peripheral blood samples and then detected the promoter methylation levels of RUNX2 using quantitative methylation-specific PCR. Relationships between UF concentration, RUNX2 promoter methylation and BMD changes were analyzed using generalized linear model and logistic regression. Results showed in EFG (UF concentration > 1.6 mg/L), BMD was negatively correlated with UF concentration (ß: -0.14; 95%CI: -0.26, -0.01) and RUNX2 promoter methylation (ß: -0.13; 95%CI: -0.22, -0.03) in women. The methylation rate of RUNX2 promoter increased by 2.16% for each 1 mg/L increment in UF concentration of women in EFG (95%CI: 0.37, 3.96). No any significant associations between UF concentration, RUNX2 promoter methylation, and BMD were observed in the individuals in CG. Mediation analysis showed that RUNX2 promoter methylation mediated 18.2% (95% CI: 4.2%, 53.2%) of the association between UF concentration and BMD of women in EFG. In conclusion, excessive fluoride exposure (>1.6 mg/L) is associated with changes of BMD in women, and this association is mediated by RUNX2 promoter methylation.

Dual-emission carbon dots achieved by luminescence center modulation within one-pot synthesis for a fluorescent ratiometric probe of pH, Hg2+, and glutathione.

Dual-emission carbon dots were synthesized by one-pot hydrothermal pyrolysis of citric acid and polyethyleneimine in the presence of rhodamine B at 160 °C for 5 h. The carbon dots have an average diameter of 2.51 nm with rhodamine moiety on their surface. Two emission bands centered at 447 and 581 nm are exhibited in their fluorescence spectra excited at 360 nm, and the former is sensitive while the latter is insensitive to Hg2+ and pH. Glutathione (GSH) can recover the fluorescence quenched by Hg2+. Therefore, the dual-emission carbon dots were developed as a fluorescent ratiometric probe employing the ratio of the two intensities at 447 and 581 nm (RI447/I581) as the signal for the determinations of pH, Hg2+, and GSH. In the range of 5.0-10.0, a good linear relationship between RI447/I581 and pH was built with a regression equation of RI447/I581 = 11.95-0.56 pH (R2 = 0.998). In the range from 0.0 to 8.0 µM, an excellent linear relationship between RI447/I581 and the concentration of Hg2+ was obtained with a calibration equation of RI447/I581 = 6.2317-0.4458c (R2 = 0.995) and a limit of detection (LOD) of 0.24 µM. In the range from 1.0 to 10.0 µM, a linear equation, RI447/I581 = 1.9133-0.4157c (R2 = 0.995), was calibrated between RI447/I581 and the concentration of glutathione with a LOD of 0.27 µM. The recoveries for the determinations of Hg2+ and GSH in real samples were in the ranges of 94.6 to 103.8% and 94.3 to 104.2%, respectively. Graphical abstract Dual-emission carbon dots achieved by luminescence center modulation within one-pot synthesis for a fluorescent ratiometric probe of pH, Hg2+, and glutathione.

Predicted concentrations of anticancer drugs in the aquatic environment: What should we monitor and where should we treat?

Anticancer drugs have been detected in the aquatic environment, they have a potent mechanism of action and their consumption is expected to drastically increase in the future. Consequently, it is crucial to routinely monitor the occurrence of anticancer drugs and to develop effective treatment options to avoid their release into the environment. Prior to implementing a monitoring program, it is important to define which anticancer drugs are more prone to be found in the surface waters. In this study the consumption of anticancer drugs in the Lisbon region (Portugal), Belgium and Haryana state (India) were used to estimate the concentrations that can be expected in surface waters. Moreover, one important aspect is to define the major entry route of anticancer drugs in the aquatic environment: is it hospital or household effluents? The results disclosed in this study showed that in Belgium and Lisbon, 94 % of the total amount of anticancer drugs were delivered to outpatients, indicating that household effluents are the primary input source of these drugs and thus, upgrading the treatment in the domestic wastewater facilities should be the focus.

Assessment of YAP gene polymorphisms and arsenic interaction in Mexican women with breast cancer.

The identification of gene-environment interactions related to breast cancer reveals the biological and molecular mechanisms underlying the disease and allows the distinction of women at high risk from women at lower risk, which could decrease the morbimortality of this neoplasm. The current study evaluated the association between polymorphisms rs1820453 and rs11225161 of the Yes-associated protein (YAP) gene in women with breast cancer exposed to arsenic (As) through drinking water. In total, 182 women were assessed for the frequency of YAP rs1820453 and rs11225161 polymorphisms and As urinary levels. The results demonstrated a positive and significant association between breast cancer and smoking, type of drinking water, and levels of AsIII , AsV and inorganic As (iAs) but not the YAP gene polymorphisms evaluated. In conclusion, our data showed that the source of drinking water and AsV and iAs urinary levels increased the risk for breast cancer, but no interactions between YAP gene polymorphisms and As urinary levels were found.

Effects of secondary biological treatment plant effluent administration, as drinking water, to rats' urogenital system in relation to cadmium and lead accumulation.

The aim of this study was to examine the effect of the secondary biological treatment plant effluent administration on the kidneys, urinary bladder, and testis of Wistar rats in relation to lead (Pb) and cadmium (Cd) accumulation, since such an effluent is used for irrigation of edible plants. Male Wistar rats, randomly assigned into 5 groups, were treated with domestic sewage effluent (DSE) for 24 months. Cadmium and lead concentrations in the DSE, rats' tissues, and urine were estimated by means of atomic spectroscopy. Lead was rapidly accumulated in high amounts in rats' kidney and to a lesser extent in the testis whereas Cd concentration was raised in all tissues examined. Deposition of Cd and Pd in the kidney of the rats resulted in profound damage over time. The results showed that long-term administration to DSE as drinking water exposes living organisms to urogenital stress related to heavy metal concentration and pH of the effluent.

Association of Arsenic Exposure with Whole Blood DNA Methylation: An Epigenome-Wide Study of Bangladeshi Adults.

BACKGROUND: Arsenic exposure affects [Formula: see text] people worldwide, including [Formula: see text] in Bangladesh. Arsenic exposure increases the risk of cancer and other chronic diseases, and one potential mechanism of arsenic toxicity is epigenetic dysregulation. OBJECTIVE: We assessed associations between arsenic exposure and genome-wide DNA methylation measured at baseline among 396 Bangladeshi adults participating in the Health Effects of Arsenic Longitudinal Study (HEALS) who were exposed by drinking naturally contaminated well water. METHODS: Methylation in whole blood DNA was measured at [Formula: see text] using the Illumina InfiniumMethylationEPIC (EPIC) array. To assess associations between arsenic exposure and CpG methylation, we used linear regression models adjusted for covariates and surrogate variables (SVs) (capturing unknown technical and biologic factors). We attempted replication and conducted a meta-analysis using an independent dataset of [Formula: see text] from 400 Bangladeshi individuals with arsenical skin lesions. RESULTS: We identified 34 CpGs associated with [Formula: see text] creatinine-adjusted urinary arsenic [[Formula: see text]]. Sixteen of these CpGs annotated to the [Formula: see text] array, and 10 associations were replicated ([Formula: see text]). The top two CpGs annotated upstream of the ABR gene (cg01912040, cg10003262 ). All urinary arsenic-associated CpGs were also associated with arsenic concentration measured in drinking water ([Formula: see text]). Meta-analysis ([Formula: see text] samples) identified 221 urinary arsenic-associated CpGs ([Formula: see text]). The arsenic-associated CpGs from the meta-analysis were enriched in non-CpG islands and shores ([Formula: see text]) and depleted in promoter regions ([Formula: see text]). Among the arsenic-associated CpGs ([Formula: see text]), we observed significant enrichment of genes annotating to the reactive oxygen species pathway, inflammatory response, and tumor necrosis factor [Formula: see text] ([Formula: see text]) signaling via nuclear factor kappa-B ([Formula: see text]) hallmarks ([Formula: see text]). CONCLUSIONS: The novel and replicable associations between arsenic exposure and DNA methylation at specific CpGs observed in this work suggest that epigenetic alterations should be further investigated as potential mediators in arsenic toxicity and as biomarkers of exposure and effect in exposed populations. https://doi.org/10.1289/EHP3849.

Dispersed Solidified Fine Droplets Based on Sonication of a Low Melting Point Deep Eutectic Solvent: a Novel Concept for Fast and Efficient Determination of Cr(VI) in Urine Samples.

Cr(VI) has carcinogenic effects, so determination of trace amount of chromium in human body such as urine has a great deal of importance. In this work, a novel microextraction method was developed based on solidification of dispersed fine droplets (SDFD) of a low melting point deep eutectic solvent (DES), produced with the aid of sonication, for fast and efficient determination of Cr(VI) in urine samples. Cr(VI) contents of the human urine samples were first complexed using 1,5-diphenylcarbazone at pH ≈ 2.0 and then extracted by the method. A cloudy solution was achieved by the sonication of a microliter volume of a new water-immiscible DES consisting of benzyltriphenylphosphonium bromide (BTPPB) and phenol. Low freezing point of DES makes it possible to use simple, precise, and fast collection of the extraction phase by solidification and the subsequent centrifugation. Finally, the sedimented phase was diluted with methanol and analyzed by electrothermal atomic absorption spectrometry (ETAAS). The influences of the main factors on the efficiency of the procedure were investigated by a four-factor central composite design (CCD). Under the optimum conditions, the calibration curve was linear within the range of 10-1000 ng L-1. The intra- and inter-day RSD% values of 2.6 and 4.7% were obtained at the concentration of 50.0 ng L-1, respectively. The limits of detection (LOD) and quantification (LOQ) were calculated as 2.0 and 7.0 ng L-1, respectively. Moreover, compared to the other approaches, the proposed method presented better or comparable analytical performance and provided accurate, precise, and reliable results for trace analysis of Cr(VI) in urine samples.

Assessment of arsenic species in human hair, toenail and urine and their association with water and staple food.

Arsenic intake from household drinking/cooking water and food may represent a significant exposure pathway to induce cancer and non-cancer health effects. This study is based on the human biomonitoring of 395 volunteers from 223 households with private water sources located in rural Punjab, Pakistan. This work has shown the relative contribution of water and staple food to arsenic intake and accumulation by multiple biological matrix measurements of inorganic and organic arsenic species, while accounting for potential confounders such as age, gender, occupation, and exposure duration of the study population. Multi-variable linear regression showed a strong significant relationship between total arsenic (tAs) intake from water and concentrations of tAs, inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) in urine and toenail samples. tAs intake from staple food (rice and wheat) also showed a strong significant relationship with hair tAs and iAs. The sole impact of staple food intake on biomarkers was assessed and a significant correlation was found with all of the urinary arsenic metabolites. Toenail was found to be the most valuable biomarker of past exposure to inorganic and organic arsenic species of dietary and metabolic origin.

Effect of a Supplementation with Two Quelites on Urinary Excretion of Arsenic in Adolescents Exposed to Water Contaminated with the Metalloid in a Community in the State of Guanajuato, Mexico.

Quelites are Mexican wild plants, reported as excellent sources of nutritional compounds such as amino acids (serine, glycine, and cysteine), minerals (Mg, Fe, and Zn), and phytochemicals, as phenolic acids (chlorogenic acid) and flavonoids (phloridzin and naringenin); on the other hand, high biological activity has been shown in these compounds. This work aimed to evaluate the effect of a supplementation with two endemic quelites of Mexico (Chenopodium berlandieri L. and Portulaca Oleracea L.); in addition to supplementation, a nutritional intervention was performed; the biomarkers of hemoglobin (Hb), urinary malondialdehyde (UMDA), and urinary arsenic (UAs) were measured in adolescents exposed to arsenic. A clinical intervention study was conducted in 27 adolescents ages 11 to 12 years for 4 weeks. Weekly anthropometric and dietary evaluations were carried out, as well as the concentration of Hb; the UMDA and UAs were performed by plate-based colorimetric measurement and atomic absorption spectrophotometry with the hydrides generation system, respectively. The results showed that UMDA concentrations had a significant improvement in the supplemented group (SG) vs. control group (CG) (SG = 1.59 ± 0.89 µM/g creatinine vs. CG = 2.90 ± 0.56 µM/g creatinine) in the second week of intervention; on the other hand, the supplemented group showed an increase in Hb levels (15.12 ± 0.99 g/dL) in the same week; finally after the second week, an increase in UAs levels was observed significantly compared to the baseline value (Baseline: 56.85; Week 2: 2.02 µg/g creatinine). Therefore, the results show that the mixture of quelites (a rich source of phytochemicals and nutrients) improved hemoglobin and UMDA levels, and urinary arsenic excretion from the second week in the exposed population.

Dietary flavonoids improve urinary arsenic elimination among Mexican women.

Inorganic arsenic (iAs) exposure increases risk of several diseases, including cancer. Some nutrients such as flavonoids enhance glutathione activity, which in turn play a key role in iAs elimination. Our objective was to explore whether dietary non-soy flavonoids are associated with iAs metabolism. We hypothesized that the intake of flavonoids belonging to the following groups, flavan-3-ols, flavone, flavonol, flavanone, and anthocyanidin, is positively associated with urinary dimethylarsinic acid (DMA), which is the most soluble iAs metabolite excreted. We performed a cross-sectional study that included 1027 women living in an arsenic-contaminated area of northern Mexico. Flavonoid intake was estimated using a validated food frequency questionnaire. Concentration of urinary iAs and its metabolites (monomethylarsonic acid and DMA) were determined by high performance liquid chromatography ICP-MS. Results showed positive significant associations between DMA and the flavonoid groups flava-3-ols (ß= 0.0112) and flavones (ß= 0.0144), as well as the individual intake of apigenin (ß= 0.0115), luteolin (ß= 0.0138), and eriodictyol (ß= 0.0026). Our findings suggest that certain non-soy flavonoids may improve iAs elimination; however, there is still very limited information available regarding the consumption of flavonoids and iAs metabolism.

Evaluation of kidney injury biomarkers in an adult Mexican population environmentally exposed to fluoride and low arsenic levels.

Fluoride (F) is a toxicant widely distributed in the environment. Experimental studies have shown kidney toxicity from F exposure. However, co-exposure to arsenic (As) has not been considered, and epidemiological information remains limited. We evaluated the association between F exposure and urinary kidney injury biomarkers and assessed As co-exposure interactions. A cross-sectional study was conducted in 239 adults (18-77 years old) from three communities in Chihuahua, Mexico. Exposure to F was assessed in urine and drinking water, and As in urine samples. We evaluated the urinary concentrations of albumin (ALB), cystatin-C (Cys-C), kidney injury molecule 1 (KIM-1), clusterin (CLU), osteopontin (OPN), and trefoil factor 3 (TFF-3). The estimated glomerular filtration rate (eGFR) was calculated using serum creatinine (Creat) levels. We observed a positive correlation between water and urine F concentrations (ρ = 0.7419, p < 0.0001), with median values of 1.5 mg/L and 2 µg/mL, respectively, suggesting that drinking water was the main source of F exposure. The geometric mean of urinary As was 18.55 ng/mL, approximately 39% of the urine samples had As concentrations above the human biomonitoring value (15 ng/mL). Multiple linear regression models demonstrated a positive association between urinary F and ALB (ß = 0.56, p < 0.001), Cys-C (ß = 0.022, p = 0.001), KIM-1 (ß = 0.048, p = 0.008), OPN (ß = 0.38, p = 0.041), and eGFR (ß = 0.49, p = 0.03); however, CLU (ß = 0.07, p = 0.100) and TFF-3 (ß = 1.14, p = 0.115) did not show significant associations. No interaction with As exposure was observed. In conclusion, F exposure was related to the urinary excretion of early kidney injury biomarkers, supporting the hypothesis of the nephrotoxic role of F exposure.

Fluoride-associated ultrastructural changes and apoptosis in human renal tubule: a pilot study.

The susceptibility of the kidneys to fluoride toxicity can largely be attributed to its anatomy and function. As the filtrate moves along the complex tubular structure of each nephron, it is concentrated in the proximal and distal tubules and collecting duct. It has been frequently observed that the children suffering from renal impairments also have some symptoms of dental and skeletal fluorosis. The findings suggest that fluoride somehow interferes with renal anatomy and physiology, which may lead to renal pathogenesis. The aim of this study was to evaluate the fluoride-associated nephrotoxicity. A total of 156 patients with childhood nephrotic syndrome were screened and it was observed that 32 of them had significantly high levels ( p ≤ 0.05) of fluoride in urine (4.01 ± 1.83 ppm) and serum (0.1 ± 0.013 ppm). On the basis of urinary fluoride concentration, patients were divided into two groups, namely group 1 (G-1) ( n = 32) containing normal urine fluoride (0.61 ± 0.17 ppm) and group 2 (G-2) ( n = 32) having high urine fluoride concentration (4.01 ± 1.83 ppm). Age-matched healthy subjects ( n = 33) having normal levels of urinary fluoride (0.56 ± 0.15 ppm) were included in the study as control (group 0 (G-0)). Kidney biopsies were taken from G-1 and G-2 only, who were subjected to ultrastructural (transmission electron microscopy) and apoptotic (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling) analysis. Various subcellular ultrastructural changes including nuclear disintegration, chromosome condensation, cytoplasmic ground substance lysis, and endoplasmic reticulum blebbing were observed. Increased levels of apoptosis were observed in high fluoride group (G-2) compared to normal fluoride group (G-1). Various degrees of fluoride-associated damages to the architecture of tubular epithelia, such as cell swelling and lysis, cytoplasmic vacuolation, nuclear condensation, apoptosis, and necrosis, were observed.

Using urine as a biomarker in human exposure risk associated with arsenic and other heavy metals contaminating drinking groundwater in intensively agricultural areas of Thailand.

Urine used as a biomarker was collected and compared between two groups of participants: (1) a groundwater-drinking group and (2) a non-groundwater-drinking group in intensively agricultural areas in Ubon Ratchathani province, Thailand. The statistical relationship with the metal concentration in shallow groundwater wells was established with urine data. According to the groundwater data, the health risk assessment results for four metals appeared to be higher for participants who drank groundwater than for the other group. The carcinogenic risk and non-carcinogenic risk of arsenic (As) were found in 25.86 and 31.03% of participants, respectively. For lead (Pb), 13.79% of the participants had a non-carcinogenic risk. Moreover, 30 of the 58 participants in the groundwater-drinking group had As urine higher than the standard, and 26, 2 and 9 of the 58 participants had above-standard levels for cadmium (Cd), Pb and mercury (Hg) in urine, respectively. Both the risk assessment and biomarker level of groundwater-drinking participants were higher than in the other group. The results showed an average drinking rate of approximately 4.21 ± 2.73 L/day, which is twice as high as the standard. Interestingly, the As levels in the groundwater correlated with those in the urine of the groundwater-drinking participants, but not in the non-groundwater-drinking participants, as well as with the As-related cancer and non-carcinogenic risks. The hazard index (HI) of the 100 participants ranged from 0.00 to 25.86, with an average of 1.51 ± 3.63 higher than the acceptable level, revealing that 28 people appeared to have non-carcinogenic risk levels (24 and 4 people for groundwater-drinking participants and non-groundwater-drinking participants, respectively). Finally, the associated factors of heavy metals in urine were the drinking water source, body weight, smoking, sex and use of personal protective equipment.

Associations between prenatal arsenic exposure with adverse pregnancy outcome and child mortality.

BACKGROUND: Chronic arsenic exposure is a public health concern in many parts of the world, with elevated concentrations in groundwater posing a threat to millions of people. Arsenic is associated with various cancers and an array of chronic diseases; however, the relationship with adverse pregnancy outcomes and child mortality is less established. OBJECTIVES: We evaluated associations between individual-level prenatal arsenic exposure with adverse pregnancy outcomes and child mortality in a pregnancy study among 498 women nested in a larger population-based cohort in rural Bangladesh. METHODS: Creatinine-adjusted urinary total arsenic concentration, a comprehensive measure of exposure from water, food, and air sources, reflective of the prenatal period was available for participants. Self-reported pregnancy outcomes (livebirth, stillbirth, spontaneous/elective abortion) were ascertained. Generalized estimating equations, accounting for multiple pregnancies of participants, were used to estimate odds ratios and 95% confidence intervals in relation to adverse pregnancy outcomes. Vital status of livebirths was subsequently ascertained through November 2015. Cox proportional hazards models were used to estimate hazard ratios and 95% confidence intervals in relation to child mortality. RESULTS: We observed a significant association between prenatal arsenic exposure and the risk of stillbirth (greater than median; adjusted OR = 2.50; 95% CI = 1.04, 6.01). We also observed elevated risk of child mortality (greater than median; adjusted HR = 1.92; 95% CI = 0.78, 4.68) in relation to prenatal arsenic exposure. CONCLUSIONS: Prospective studies should continue to evaluate prenatal and early life health effects of arsenic exposure and arsenic remediation strategies for women of child-bearing age.

High exposure to boron in drinking water and sperm parameters in Chilean young people / Exposición elevada a boro en el agua potable y parámetros de esperma en gente joven chilena

Our aim was to describe sperm parameters in residents from Northern Chile. We evaluated in 101 volunteers (18 and 30 years old) urinary and drinking water Boron levels using Inductively Coupled Plasma Mass Spectrometry; semen parameters were measured with standardized methods. Each individual was categorized in 3 levels of exposure: low (B levels in urine 2.94 mgL-1 or tap water 3.0 mgL-1), medium (urinary B between 2.95-7.4 mgL-1 and B in tap water with 3.0-7.0 mgL-1) and high (urinary B > 7.4 mgL-1 or tap water > 7.0 mgL-1). We found no significant differences among groups by pH, sperm concentration (45.1; 48.2 and 38 million/mL), motility 1th hour (38.1; 40.0 and 45.5 %) and vitality 1th hour (88.6; 88.0 and 76.9 %) respectively. Abnormal morphology was significant different (83.3; 90 and 83 %). Young men exposed to B in drinking water present sperm variations associated with the level of exposure. Most of these changes are positive at intermediate levels of B. For the highest exposures were observed negative changes in sperm morphology, concentration, motility and vitality, all relevant parameters of fertility. Beneficial effect is observed at medium exposure, like a "U curve".

El objetivo de este trabajo fue describir los parámetros espermáticos en residentes del norte de Chile. Se evaluaron en 101 voluntarios (18 y 30 años), los niveles urinarios y de agua potable de boro, usando "Inductively Coupled Plasma Mass Spectrometry". Los parámetros del semen se midieron con métodos estandarizados. Cada individuo se clasificó en 3 niveles de exposición: bajo (niveles B en la orina 2,94 mgL-1 o agua potable 3,0 mgL-1), medio (B urinario entre 2,95-7,4 mgL-1 y B en agua de beber con 3,0- 7,0 mgL-1) y alto (B urinario >7,4 mgL-1 o agua potable > 7,0 mgL-1). No se encontraron diferencias significativas entre los grupos por pH, concentración de espermatozoides (45,1; 48,2 y 38 millones/mL), motilidad a 1 hora (38,1; 40,0 y 45,5%) y vitalidad 1 hora (88,6; 88,0 y 76,9%) respectivamente. La morfología anormal fue significativamente diferente (83,3; 90 y 83%). Los hombres jóvenes expuestos a B en el agua potable presentan variaciones espermáticas asociadas con el nivel de exposición. La mayoría de estos cambios son positivos en niveles intermedios de B. Para las exposiciones más altas se observaron cambios negativos en la morfología, concentración, motilidad y vitalidad del esperma, parámetros relevantes de la fertilidad. Un efecto beneficioso se observa en la exposición media, como una "curva U".

Increased microRNA 21 expression contributes to arsenic induced skin lesions, skin cancers and respiratory distress in chronically exposed individuals.

More than 26 million people in West Bengal, India, are exposed to arsenic through drinking water, leading to several deleterious endpoints including precancerous and cancerous skin lesions and other non-dermatological health effects. Here, our aim was to identify whether miR21 is associated with such dermatological and non-dermatological health outcomes in chronically exposed humans. A total of 123 subjects from West Bengal were recruited for this study (45 exposed individuals with skin lesions, 38 exposed individuals without skin lesions and 40 unexposed individuals). The miR21 expression patterns in the lymphocytes were studied by quantitative realtime PCR and the effects on downstream targets were validated by Western blotting. Associations between the miR21 expression patterns and non-dermatological health effects were determined from epidemiological survey data. In vitro studies were done with low dose (0.05ppm) of chronic arsenic exposure to HaCaT cells for 15 passages. Interestingly, within the exposed group, the skin lesion individuals showed almost 4.5 fold up-regulation of miR21 compared to the no skin lesion group. The expression of the downstream targets of miR21 (PTEN and PDCD4) varied inversely, while the expression of pAKT and PI3K varied proportionately with its expression levels. Results of in vitro studies showed similar trends. Again miR21 was 2.03 fold up-regulated in the exposed individuals with respiratory diseases compared to the individuals without the same. This study for the first time shows that miR21 plays an important role in contributing to arsenic induced dermatological and non-dermatological health outcomes in an exposed population.

Association between polymorphisms in arsenic metabolism genes and urinary arsenic methylation profiles in girls and boys chronically exposed to arsenic.

Disease manifestations or susceptibilities often differ among individuals exposed to the same concentrations of arsenic (As). These differences have been associated with several factors including As metabolism, sex, age, genetic variants, nutritional status, smoking, and others. This study evaluated the associations between four As metabolism-related gene polymorphisms/null genotypes with urinary As methylation profiles in girls and boys chronically exposed to As. In a total of 332 children aged 6-12 years, the frequency of AS3MT, GSTO1, GSTT1, and GSTM1 polymorphisms/null genotypes and As urinary metabolites were measured. The results revealed that total As and monomethyl metabolites of As (MMA) levels were higher in boys than in girls. No differences in the frequency of the evaluated polymorphisms were found between girls and boys. In AS3MT-Met287Thr carriers, %MMA levels were higher and second methylation levels (defined as dimethylarsinic acid divided by MMA) were lower. In children with the GSTM1 null genotype, second methylation levels were higher. In boys, a positive association between the AS3MT-Met287Thr polymorphism with %MMA and between the GSTO1-Glu155del and As(v) was found; whereas, a negative relationship was identified between AS3MT-Met287Thr and second methylation profiles. In girls, a positive association was found between the GSTO1-Ala140Asp polymorphism with second methylation levels. In conclusion, our data indicate that gender, high As exposure levels, and polymorphisms in the evaluated genes negatively influenced As metabolism. Environ. Mol. Mutagen. 57:516-525, 2016. © 2016 Wiley Periodicals, Inc.

Association between exposures to brominated trihalomethanes, hepatic injury and type II diabetes mellitus.

Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver disorder in the Western world, commonly diagnosed in the majority of obese patients with type 2 diabetes mellitus (T2DM). Metabolic disrupting chemicals with short half-lives, such as those of halogenated structure (trihalomethanes, THM) have been linked with hepatic insulin resistance phenomena in animal studies. However, human studies evaluating the role of THM exposure on liver pathogenesis and T2DM disease process are scarce. The objectives of this study were to: i) determine the association of urinary brominated THM (BrTHM) levels and T2DM disease status, and ii) investigate the association between urinary BrTHM levels and serum alanine aminotransferase (ALT) concentrations, often used as surrogate markers of NAFLD. A pilot case-control study was conducted in Nicosia, Cyprus (n=95). Cases were physician-diagnosed T2DM patients and controls were healthy individuals. Liver enzymes, leptin and TNF-α were measured in sera, while urinary THM levels were measured using tandem mass spectrometry. Diabetics had higher levels of serum leptin, body mass index and ALT than the controls. Among all study participants those with serum ALT levels above the median (17IU/L) had higher mean tribromomethane (TBM) concentrations compared to those with serum ALT below 17IU/L. A significant increase in the odds of having above the median serum ALT levels [OR 6.38, 95% CI: 1.11, 42.84 (p=0.044)] was observed for each unit increase in creatinine-unadjusted urinary TBM levels, along with BMI and past smoking, after adjusting for possible confounders, such as urinary creatinine, age, sex, and leptin; no other THM compound showed a significant association with serum ALT. Logistic regression models for T2DM using the urinary BrTHM as exposure variables did not reach the predetermined level of significance. The interplay between exposures to BrTHM and the initiation of key pathophysiological events relating to hepatic injury (ALT) and inflammation (leptin) was recognized via the use of selected biomarkers of effect. Our evidence that THM could act as hepatic toxins with a further initiation of diabetogenic effects call for additional studies to help us better understand the disease process of the two co-morbidities (NAFLD and T2DM).

Association of cadmium and arsenic exposure with salivary telomere length in adolescents in Terai, Nepal.

BACKGROUND: Cadmium and arsenic are ubiquitous metals commonly found in the environment which can harm human health. A growing body of research shows telomere length as a potential biomarker of future disease risk. Few studies have examined the effects of metals on telomere length and none have focused on adolescents. OBJECTIVES: In this study, the impact of cadmium and arsenic on salivary telomere length was studied in adolescents in Terai, Nepal. METHODS: Adolescents aged 12-16 years old (n=351)were recruited where questionnaire interviews and both saliva and urine collection took place. Telomere length was determined by quantitative polymerase chain reaction using DNA extracted from saliva. Urinary cadmium and arsenic concentration were measured by inductively coupled plasma mass spectrometry. Multivariable linear regression was used to examine associations between urinary metals and salivary telomere length. RESULTS: The geometric means and standard deviations of cadmium and arsenic were 0.33±0.33µg/g creatinine and 196.0±301.1µg/g creatinine, respectively. Urinary cadmium concentration was negatively associated with salivary telomere length after adjustment for confounders (ß=-0.24, 95% CI -0.42,-0.07). Arsenic showed positive associations with telomere length but did not reach statistical significance. CONCLUSIONS: This is the first study to demonstrate that cadmium may shorten adolescent telomeres, even at exposure levels that may be considered low. These results agree with prior experimental and adult epidemiological studies, and also help identify the mechanism of DNA damage by cadmium. This study expanded current evidence on the harmful effects of cadmium exposure on telomere length even to adolescents.

Use of microextraction by packed sorbents and gas chromatography-mass spectrometry for the determination of polyamines and related compounds in urine.

A novel methodology for the determination of ornithine, putrescine, cadaverine, spermidine and gamma-amino butyric acid in urine samples has been developed. The method uses in situ aqueous derivatization followed by automated microextraction by packed sorbent coupled to a gas chromatography-mass spectrometry system equipped with a programmed temperature vaporizer. This instrumental configuration minimizes sample manipulation due to from the mixing of the reagents, the process is completely automated. The analytes were derivatized using ethyl chloroformate as derivatization reagent. The reaction occurred in aqueous medium and was carried out in 1min in the vial of an autosampler used to perform microextraction by packed sorbent. The parameters affecting derivatization, extraction and separation were optimized in order to obtain maximum sensitivity. Calibration curves were obtained for five calibration levels in three different matrices. All the calibration models displayed good linearity, with R(2) values higher than 0.95. The validity of the models was checked using ANOVA, and it was observed that they did not exhibit any lack of fit. Repeatability and reproducibility was evaluated, with values below 15% in both cases. LOD and LOQ values were found to be in the low µg/L level. Influence of the matrix was confirmed, thus quantification was performed using the standard additions method and normalization to IS. The method developed was applied to the analysis of these compounds in urine samples from healthy individuals and cancer diagnosed patients (Internal Medicine Unit of the Virgen de la Vega Hospital, Salamanca, Spain). Significant differences (Mann-Whitney U test) were observed for putrescine and ornithine concentrations.